2000-12-25
initdb
1
Application
initdb
Create a new Postgres database cluster
initdb
--pgdata
-D
dbdir
--sysid
-i
sysid
--pwprompt-W
--encoding
-E
encoding
-L directory
--noclean-n
--debug-d
Description
initdb creates a new
Postgres database cluster or system. A
database cluster is a collection of databases that are managed by a
single postmaster.
Creating a database system consists of creating the directories in which
the database data will live, generating the shared catalog tables
(tables that belong to the whole cluster rather than to any particular
database), and creating the template1
database. When you create a new database, everything in the
template1 database is copied.
It contains catalog tables filled in for things like the
built-in types.
You must not execute initdb as root; it must
be run by the Unix user account that will run the database server.
This is because you cannot run the database server as root either, but the
server needs to have access to the files initdb
creates. Furthermore, during the initialization phase, when there are no
users and no access controls installed, Postgres
will only connect with
the name of the current Unix user, so you must log in under the account
that will own the server process.
Although initdb will attempt to create the
specified data directory, often it won't have permission to do so,
since the parent of the desired data directory is often a root-owned
directory. To set up an arrangement like this, create an empty data
directory as root, then use chown to hand over
ownership of that directory to the database user account, then
su to become the database user, and
finally run initdb as the database user.
Options
--pgdata=dbdir
-D dbdir
This option specifies where in the file system the database
should be stored. This is the only information required by
initdb, but you can avoid writing it by
setting the PGDATA environment variable, which
can be convenient since the database server
(postmaster) can find the database
directory later by the same variable.
--sysid=sysid
-i sysid
Selects the system id of the database superuser. This defaults
to the effective user id of the user running
initdb. It is really not important
what the superuser's sysid is, but one might choose to start
the numbering at some number like 1.
--pwprompt
-W
Makes initdb prompt for a password
to give the database superuser. If you don't plan on using password
authentication, this is not important. Otherwise you won't be
able to use password authentication until you have a password
set up.
--encoding=encoding
-E encoding
Selects the multibyte encoding of the template database. This will also
be the default encoding of any database you create later, unless you
override it there. To use the multibyte encoding feature, you must
specify so at build time, at which time you also select the default
for this option.
Other, less commonly used, parameters are also available:
-L directory
Specifies where initdb should find
its input files to initialize the database system. This is
normally not necessary. You will be told if you need to
specify their location explicitly.
--noclean
-n
By default, when initdb
determines that an error prevented it from completely creating the database
system, it removes any files it may have created before discovering
that it can't finish the job. This option inhibits tidying-up and is
thus useful for debugging.
--debug
-d
Print debugging output from the bootstrap backend and a few other
messages of lesser interest for the general public.
The bootstrap backend is the program initdb
uses to create the catalog tables. This option generates a tremendous
amount of extremely boring output.
See also
PostgreSQL Administrator's Guide